Which is the best scope?

This spring I had two scopes for my disposal: an 8-inch Portaball and a 12.5-inch NGT. Both scopes are Newtonians, but they quite different when comes to ease of handling as well as optical performance. Since I never looked through a 12.5-inch before I was very keen, of course, to try the NGT, and during the first weeks this was my first choice whenever the sky was clear. The NGT is equatorially mounted with clock drive, hand control and digital setting circles. But it is a heavy beast and it quite difficult to handle without a second person helping. The Portaball has no drive option and has to be pointed manually, but it is extremely easy to transport and handle.

Optically the Portaball is the better scope, and for planetary detail and appealing views of double stars the NGT could not match it in spite of 50% larger aperture.
For deep-sky purposes the NGT was the clear winner. The extra step on the magnitude scale made all star clusters much more impressive, and more detail is within range in galaxies and nebulae than in the Portaball.

I can live without digital setting circles, but I admit that they are convenient wherever there are few reference stars available.

Weight is an important issue for me. In the long run I think the Portaball would see more use than the NGT. One-man set-up time is about 30 minutes for the NGT and 2 - 3 minutes with the Portaball.

If I owned both scopes (which I don't) I would trade them for a 12.5-inch Portaball.

Inge, it sounds as if you and I agree with regard to the telescopes you mentioned. I'm not sure how important nebulae and galaxies are to *you,* but I do know that my foremost/primary/favorite viewing targets are the planets and Luna. The "dim fuzzies" are very nice, and I enjoy viewing them through telescopes at every opportunity. However, I *could* refrain from doing so without much "astro withdrawl." :-) I don't believe I could say the same about the planets. They *are* the reason I participate in this crazy hobby.

I've never been very enthusiastic about the various JMI systems, but I well understand their appeal, and I respect their designs/engineering. As for the PortaBalls, I can easily see myself owning one in the future.

Best wishes.
-Dan

I would like to emphasise, though, that the NGT is not a bad scope either. I use to keep it at outside temperature, therefore temperature equalisation is no issue (but I have to switch the heat off when driving to the observation site). And with some assistance, set-up is done in less than 10 minutes. Therefore it is a good club scope, and just fine for demo purposes when tracking is an advantage. I try to keep the balance between deep-sky, planetary and double star observation. And I can go very deep with the 8-inch Portaball under the best conditions with tremendous detail in hte Veil nebula. The 8-inch also shows absorbing clouds in some galaxies very well - I would say better than the 12.5-inch. For spirals, however, the structure is muche more easily seen with the larger aperture.

One curiosity: When I got the Portaball I was used to finderscopes with some aperture and magnification, and I struggled for a few hours getting used to the 1x QuickFinder. Within a few weeks, however, I changed my approach for locating tings, switching to triangulisation rather than star-hopping. The NGT is equipped with a 9x50 finderscope. When I started using it I felt completely lost due to the reversed image and the number of stars visible. Such a finder is definitely not suited for triangulisation. Fortunately, there is a guy in our astronomy club who loves to operate the digital setting circles.

The NGT/Portaball combo is great as long as I have somebody to observe together with. And some club members may be interested in imaging. But as a single-user general purpose visual scope, the Portaball is hard to beat. Due to the central obstruction it can not stop the mouth of the APO community, but personally I never miss a refractor.